The invention relates to a device for high-throughput screening. More particularly, the invention relates to a device for automatically feeding microplates into an analyzer for high-throughput screening.
High-throughput screening instruments (or analyzers) are critical tools in the pharmaceutical research industry and in the process of discovering and developing new drugs. High-throughput analyzers are used to assess the efficacy of candidate drug compounds. Dramatic increases in the number of these compounds and in the number of targets against which they may be directed have created a bottleneck in the development of new drugs and a need for analyzers that can operate with a high degree of analytical flexibility and speed. Analytical flexibility and speed are necessary because high-throughput applications may involve repeating the same operations hundreds of thousands of times, greatly magnifying even the smallest shortcomings.
One way to increase speed and analytical flexibility is to house a variety of small-volume samples in a single container. Toward this end, high-density containers known as microplates have been developed. Microplates are generally rectangular containers that include a plurality of sample wells for holding a plurality of samples. Microplates enhance speed by reducing transit time between samples and reduce cost by employing small amounts of reagents. Unfortunately, microplates also have a number of shortcomings. For example, microplates do not conform to any exact standard, so that their size, shape, and construction materials may vary, depending on vendor or batch. In addition, microplates may vary from opaque to transparent, so that analytical approaches developed for some microplates will not work for other microplates. Moreover, preferred microplates may differ, depending on application. Furthermore, microplates may allot only a small volume for each sample, so that signal is reduced and sample is more easily spilled during transit.
Another way to increase speed and analytical flexibility is to use robots and other devices to automate high-throughput screening procedures. For example, robots permit analyzers to run 24 hours a day. Unfortunately, current robotic systems have a number of shortcomings. For example, robots commonly are used to deliver samples to an analyzer for analysis. However, the robot typically must make separate trips to drop off a sample container, such as a microplate, before analysis, to retrieve the sample container after analysis, and then to drop off another sample container for analysis. In this approach, the analyzer is idle during the time that the robot is retuning the analyzed microplate and bringing the new microplate. As time and the number of sample containers analyzed increases, the total down time due to robotic transport may become quite significant.
Another way to increase speed and analytical flexibility problem is to permit manual or automated feeding of sample containers. Unfortunately, switching between manual and automated feeding modes with current analyzers has a number of shortcomings. For example, automated microplate feeding systems may not permit manual feeding while the automated feeder is connected to the analyzer. To use such an analyzer in a manual mode, the automatic feeder must be disconnected.
The present invention addresses these and other shortcomings by providing a sample feeder that includes (1) a first station that receives and initiates transport of a sample container into an analyzer for analysis, (2) a second station where the sample container is handed off to a transporter that carries the sample container to and from an examination site inside the analyzer, and (3) a third station that collects the sample container after examination. The sample feeder may include a singulation mechanism positioned at the first station and configured to separate a sample container from a stack of sample containers for transport to the analyzer, and/or a stacking mechanism positioned at the third station and configured to add a sample container to a stack of sample containers. The sample feeder further may include a preprocessing bin positioned at the first station for holding a stack of sample containers to be analyzed, and/or a postprocessing bin positioned at the third station for holding a stack of sample containers after they have been analyzed.
The invention also provides a sample feeder that includes (1) a lifter configured to raise or lower a sample container relative to the bottom of a stack of sample containers, and (2) at least one latch having a pick portion, the latch being mounted so that the pick portion moves in and out of gaps between adjacently stacked sample containers in response to up and down movement of the lifter. The lifter and latch may be designed to remove a single sample container from the bottom of a stack of sample containers, or to add a single sample container to the bottom of a stack of sample containers. The latch may include a pick portion that is urged toward the bottom of the stack by gravity, a spring, or other mechanisms.
The invention also provides a sample feeder that includes (1) a lifter configured to impart a raising or lowering motion to a sample container to transfer the sample container to or from a stack of sample containers, and (2) a drive motor configured to generate a driving motion, wherein the lifter includes a cam operatively connected to the drive motor and configured to convert the driving motion into the raising or lowering motion.
The invention also provides an automated analyzer system that includes (1) an analyzer unit having an internal examination site, and (2) first and second external loading stations, the first external loading station configured to receive a sample container before analysis, the second external loading station configured to receive the sample container after analysis. The automated analyzer system may include a robot programmed to deliver a sample container to the first external loading station, and to retrieve a different sample container from the second loading station in the same trip.
The invention will be understood more readily after consideration of the drawings and the detailed description of the invention that follow.